Automatic control system for locomotive whistles



FIG. 1.

Jan. 26, 1937. P. w. SMITH ET AL 2,063,934

AUTOMATIC CONTROL SYSTEM FOR LOCOMOTIVE WHISTLES Filed Oct. 17, 1934 2 Sheets-Sheet 1 INVENTORS THEIR ATTORNEY Jan. 26, 1937. P. w. SMITH ET AL 2,068,934

AUTOMATIC CONTROL SYSTEM FOR LOCOMOTIVE WHISTLES Filed Oct. 17, 1934 2 Sheets-Sheet 2 L m *0 q ob "VA'W N INVENTORS d PWfimirh and C.S.BushneH THEIR ATTORNiiY Patented Jan. 26, 1937 UNITED STATES PATENT OFFICE Percy W.

Smith and Charles S. Bushnell,

Rochester, N. Y., assignors to General Railway Signal Company, Rochester, N. Y.

Application October t, 1934, Serial No. 748,696

8 Claims.

This invention relates to a system for automatically controlling the sounding of a locomotive whistle upon the approach to highway crossings on railroads.

Generally speaking, in accordance with this invention, automatic means on the locomotive, having its operation initiated from the trackway upon the approach of the locomotive to a highway crossing, is employed to sound a locomotive whistle automatically, either giving a continuous blast until an engineman assumes control of the whistle, or a series of blasts char acteristic of the warning signal commonly used for highway crossings.

Various characteristic features and advantages of the invention will be in part apparent and in part pointed out as the description progresses.

In the accompanying drawings, Fig. 1 illustratesin a simplified and diagrammatic manner one embodiment of the invention, and Fig. 2

illustrates a modification.

Referring to Fig.1, it is contemplated that a controlling impulse will be transmitted from the trackway to the locomotive by suitable means at a predetermined distance from a highway crossing, preferably by inductive devices co-operating through an air-gap without physical contact. As illustrative of an impulse transmitting means suitable for this purpose, a trackway inductor 30 and locomotive carried receiver of the type disclosed for example in the prior patent to C. S. Bushnell, No. 1,686,434, October 2, 1928, has been illustrated diagrammatically; and since the principles and mode of operation of such an in- 35 ductiveimpulse transmitting means are explained in said patent, a brief and general explanation will be sufficient for an understanding of the present invention.

The track inductor T is in effect an inert piece 40 of iron in the form of a U-shaped laminated core protected by a suitable non-magnetic housing, and is located at the side of the track with its pole faces above the level of the track rails and at a suitable distance from the highway crossing.

45 The locomotive receiver R comprises a U-shaped laminated core, having a primary coil P on one vertical leg, and a secondary coil S on the other leg. The primary coil P is energized from a generator G, or other suitable source of direct our- 50 rent on the locomotive, in series with a resistance I, by a circuit readily traced on the drawings. A sensitive relay RI, preferably of the balanced type, such as disclosed in the patent to R. C. Leake, No. 1,696,170, December 18, 1928, is 55 normally energized by a stick circuit which may be traced from a positive side of the generator, wire 2, front contact 3 of relay RI, wires 4 and 5, secondary coil S, wire 6, relay RI, and wire I to the lower terminal of the resistance I. It will be evident that the relay RI is energized by the drop 5 of voltage across the resistance RI produced by the now of current to the primary coil P.

When the receiver R on the locomotive passes over the track inductor T, a voltage is induced in the secondary coil S to de-energize the relay RI, 10 in the manner more fully explained in the prior Patent No. 1,686,434 above mentioned. In short, the relay RI on the locomotive is automatically de-energized when the locomotive passes the track inductor T at a predetermined distance from the 15 crossing.

A relay R2 is energized by a circuit including a front contact of the relay RI, which may be traced from the positive terminal of the generator, wire 2, contact 3 of relay RI, wire 8, relay 20 R2, and wires 9 and H] back to the other terminal of the generator.

Thus, whenever relay RI is de-energized, its repeater relay R2 is de-energized.

It is contemplated that the sounding of the usual steam whistle W on the locomotive will be controlled by an air operated valve V of suitable construction, and that the operation of this valve V in turn will be controlled by an electro-pneumatic valve EPV and by a hand-operated valve I-IV within convenient reach of the engineman. In the particular arrangement shown, while the coil I2 of the electro-pneumatic valve EPV is energized, the whistle controlling valve V is connected to the hand valve HV, so that by depressing the hand lever I3, the valve I I may be opened to supply pressure from the main reservoir tothe valve V and cause the whistle to sound. When the electro-pneumatic valve EPV is de-energized, main reservoir pressure is supplied directly to the valve V to sound the whistle.

The winding I2 of the electro-pneumatic valve EPV is energized by a circuit including a front contact of relay R2 which may be traced from the positive terminal of the generator, wires I5 and I6, front contact I! of relay R2, wire I8, winding I2, and wires I 9 and I0 back to the other terminal of the generator.

Thus, when the locomotive passes, the track inductor T upon the approach to a highway crossing, the de-energization of relays RI and R2 causes de-energization of the electro-pneumatic valve EPV to sound the whistle, and the whistle will continue to sound until relay RI is again energized.

Associated with the hand-operated valve HV are electrical contacts 211, closed when the lever I3 is depressed; and the closing of these contacts establishes a shunt around the front contact 3 of relay RI, so that it may again pick up, this shunt also including contacts 22 of relay R2 closed when this relay is de-energized. The pick-up circuit for relay RI, including this shunt, may be traced from the positive terminal of the generator G, wires I5 and 2I, contacts 22 of relay R2, wire 23, contacts 20 operated by the hand lever I3, wires 24 and 5, secondary coil S, wire 6, relay RI, and wire I back to the lower terminal of the resistance I.

Thus, when the blowing of the whistle is automatically started as the train passes the track inductor upon approaching the highway crossing, the engineman by operating the hand lever I3 to close contacts 20 may cause restoration of the relay RI, which is followed by energization of relays R2 and the electro-pneumatic valve EPV to stop the automatic blowing of the whistle. If the engineman is blowing the whistle at the time of passing the track inductor T by holding down the lever I3, the contacts 20 are closed and relays RI and R2 are quickly restored, and the electro-pneumatic valve EP is de-energized only momentarily.

It will be evident that this invention provides for automatically sounding a whistle signal upon the approach to a crossing, even though the engineman is incapacitated or inattentive, of if he fails to note the approach to a crossing due to fog, or smoke. If the automatic sounding of the whistle occurs, the engineman may stop the continuous blast by operating the hand lever I3, and may thereafter sound the whistle in the usual series of blasts representing the signal for a highway crossing.

Fig. 2 illustrates another embodiment of the invention in which the locomotive whistle is automatically sounded in a series of blasts corresponding to the usual Whistle signal for highway crossings, starting at a predetermined point distant from the crossing and continued as the train approaches the crossing in accordance with the distance travelled by the train. The engineman may at any time take over the automatic control of the whistle to delay or vary the whistle signal, or to stop the sounding of the whistle if the train should stop before reaching the crossing. This modified form of the invention adds in effect to the same devices illustrated in Fig. 1 apparatus for automatically energizing and de-energizing the electro-pneumatic valve controlling the whistle at predetermined intervals of distance during the approach of the train to the highway crossing.

Referring to Fig. 2, a shaft 25 is connected by a suitable transmission 26 to the axle 21 of the 10- comotive. A gear 28 on this shaft 25 meshes with an idler gear 29 carried on an arm 30, which is adapted to be raised by a spring 3| and pulled down by a starter magnet SM. When the starter SM is de-energized, and the arm 30 is raised by the spring 3I, the idler gear 29 is meshed with a gear 32 on a cam shaft 33, so that this shaft 33 is rotated gradually in accordance with the dis tance travelled by the locomotive.

The cam shaft 33, as shown, is assumed to be rotated counter-clockwise; and spaced projections on a cam 34 carried by this shaft 33 closes contacts 35, these projections being spaced so that these contacts 35 are open for two long intervals followed by two short intervals, representing the two long and two short blasts of the whistle commonly employed for highway crossmgs.

After the cam shaft 33 has made approximately a complete revolution, 2. projection on cam 36 closes contacts 31 to mark the end of the operation and to cause the shaft to be restored to its normal position. The shaft 33 is restored to normal in the particular arrangement shown by a spring 38 connected to a flexible band 39 attached to a wheel or pulley 40 on the shaft, which is partially cut away to engage a stop M.

In the modified arrangement of Fig. 2, relays RI and R2 are energized by circuits and controlled in the same way as already described for Fig. 1. The parts are shown in the normal condition; and the electro-pneumatic valve is energized by a circuit from the positive side of the generators, wires and 46, front contact I! of relay R2, wires 41 and 48, valve EPV, and wires 49, 50, and I0 back to the other side of the generator. The starter magnet SM is also energized by a circuit from the positive side of the generator, wires 45 and 46, contact I1 and relay R2, wires 5| and wires 52, 5D, and I!) back to the other side of the generator. The contacts 35 and 31 are normally open.

When the train passes the track inductor T, and relays RI and R2 are de-energized in the manner already described, the EPV valve is de-energized to sound the whistle and at the same time the starting magnet SM is de-energized to connect the cam shaft 33 to the wheels of the locomotive. After the locomotive has advanced a predetermined distance, the first projection on the cam 34 closes the contacts 35 and establishes an auxiliary circuit for energizing the valve EPV which may be traced from the positive side of the generator, wires 45, 53 and 54, contacts 35, wire 48, valve EPV, and wires 49, 5D, and I0 back to the other side of the generator. Thus, the whistle is silenced so long as the contacts 35 are closed; and after a further distance of travel these contacts open, and the whistle is again sounded. This same operation is repeated to give the blasts of the whistle to represent the highway crossing signal.

When the train reaches a predetermined distance from the crossing, the cam 36 closes the contacts 31, thereby establishing a shunt around the stick contacts of the relay RI and providing a pick-up circuit for this relay which may be traced from the positive side of the generator, wires 45, 53, and 55, contacts 31, wires 56, 51, and 5, secondary coil S, wire 6, relay RI and wire 'I to the lower terminal of the resistance I. In this way, the relay RI is again energized and its normal stick circuit is established; and the energization of relay RI is followed by the energization of relay R2 and the starter magnet SM, thereby disconnecting the cam shaft 33 from the wheels of the locomotive, so that it may be returned to its normal or initial position by the spring 38, ready for the next operation.

The engineman, by operating the lever I3 of the hand valve HV, may close contacts 20 which, together with the wires 58 and 59, form a branch circuit in multiple with the contacts 3'! and wires and 56, so that the relay RI is re-energized to restore the apparatus to normal. In other words, the engineer by operation of the lever I3 may at any time take charge of the blowing of the whistle, and restore the cam shaft 33 to normal. If the engineman should be blowing the whistle at the time relay RI is tie-energized upon passing 7 the track inductor T, this relay RI is quickly restored, and the starting magnet SM is only momentarily de-energized if at all.

A system of this invention insures the sounding of a locomotive whistle upon the approach to a crossing, even though the engineman is inactive or incapacitated. It is contemplated that the automatic sounding of the whistle will start at a suflicient distance from the crossing with a high speed train to provide ample warning time. The engineman may forestall or cancel the automatic sounding of the whistle, and regulate the duration and spacing of the blasts by hand in accordance with the speed of the train at a certain distance from the crossing.

This particular structural organization as shown and described is merely illustrative of the nature of the invention; and various adaptations, and modifications, may be made without departing from the invention.

What we claim is:--

1. In a system for automatically sounding a locomotive whistle upon the approach to a highway crossing, means on the trackway a predetermined distance from a highway, means on the locomotive automatically means on the trackway for sounding the locomotive whistle, and manually operable means for sounding the whistle and for rendering said automatic means inactive.

2. In a system of the character described, the combination with a track device located at a predetermined distance from a highway crossing, and a locomotive carried device influenced by the track device, of means on the locomotive having its operation automatically initiated by the cooperation of said devices for sounding the locomotive whistle, and manually operable means operable for sounding the whistle and restoring said automatic means to its normal inactive condition.

3. In a system for controlling the operation of locomotive whistles, a normally energized relay on the locomotive, means responsive to the deenergization of said relay for automatically sounding the locomotive whistle, a manually operable device for sounding the whistle, means operated by said manually operable device for restoring said relay, and means partly on the locomotive and partly along the track effective at a predetermined distance from the crossing for automatically de-energizing said relay.

initiated from the 4. A system for automatically controlling locomotive whistles comprising, a normally energized stick relay on the locomotive, a normally energized electro-pneumatic valve controlled by said relay and adapted when de-energized to sound the locomotive whistle, a hand lever for controlling said whistle, contacts closed by movement of said lever to the whistle sounding position, a circuit for restoring said relay including said contacts, and means for automatically de-energizing said relay at a predetermined distance from the crossing.

5. In a locomotive whistle controlling system, means on the locomotive driven from the wheels thereof and having its operation automatically initiated from the trackway upon the approach of a locomotive to a highway crossing for sounding the locomotive whistle in a series of blasts, and manually operable means for restoring said means to normal.

6. In a system of the character described, means partly on the locomotive and partly on the track for transmitting controlling impulses from the trackway to the locomotive at a predetermined distance from a highway crossing, means on the locomotive responsive to said impulses for sounding the locomotive whistle, and means also responsive to said impulses and driven from the wheels of the locomotive for silencing the whistle at predetermined points relative to the crossing.

7. A locomotive equipment for automatically sounding the whistle comprising, means having its operation automatically initiated from the trackway for sounding the whistle in a series of blasts in accordance with the distance travelled by the locomotive, and manually operable means operable to sound the Whistle and to restore said automatic means to its normal inactive condition.

8. A locomotive equipment for automatically sounding the whistle comprising, means having its operation automatically initiated from the trackway for sounding the Whistle in a series of blasts in accordance with the distance travelled by the locomotive, a second means for automatically silencing the whistle in accordance with distance travelled, and manually operable means operable to sound the whistle and to restore said automatic means to its normal inactive condition.

PERCY W. SMITH. CHARLES S. BUSHNELL. 

